- Metrics for `RetroactiveDefaultStorageClass` feature are now available. To see an attempt count for updating PVC retroactively with a default StorageClass see `retroactive_storageclass_total` metric and for total numer of errors see `retroactive_storageclass_errors_total`. ([#113323](https://github.com/kubernetes/kubernetes/pull/113323), [@RomanBednar]...

[kubernetes-server-linux-s390x.tar.gz](https://dl.k8s.io/v1.6.0/kubernetes-server-linux-s390x.tar.gz) | `e15de8896bd84a9b74756adc1a2e20c6912a65f6ff0a3f3dfabc8b463e31d19b`

## WARNING: etcd backup strongly recommended

Before updating to 1.6, you are strongly recommended to back up your etcd data.
Please consult the installation procedure you are using (kargo, kops, kube-up,
kube-aws, kubeadm etc) for specific advice.

- Fix invalid VMSS updates due to incorrect cache ([#89002](https://github.com/kubernetes/kubernetes/pull/89002), [@ArchangelSDY](https://github.com/ArchangelSDY)) [SIG Cloud Provider]
- Fix the VMSS name and resource group name when updating Azure VMSS for LoadBalancer backendPools ([#89337](https://github.com/kubernetes/kubernetes/pull/89337), [@feiskyer](https://github.com/feiskyer)) [SIG Cloud Provider]

Before updating the configuration, let's start with `mc admin config get` command to get the current configuration.

```sh
$ mc admin config get myminio/ notify_mysql

- Fix: ignore not a VMSS error for VMAS nodes in EnsureBackendPoolDeleted. (#105404, @ialidzhikov) [SIG Cloud Provider]
- Fix: ignore the case when updating Azure tags (#104687, @nilo19) [SIG Cloud Provider]
- Revert PR #102925 which introduced unexpected scheduling behavior based on balanced resource allocation (#105239, @damemi) [SIG Scheduling]

are hence enabled by default. This will be fixed in a future release.
[#38593](https://github.com/kubernetes/kubernetes/issues/38593)
* Federation control plane can be upgraded by updating the image
fields in the `Deployment` specs of the control plane components.
However, federation control plane upgrades were not tested in this
release [38537](https://github.com/kubernetes/kubernetes/issues/38537)

* Re-enable nodeipam controller for external clouds.  ([#63049](https://github.com/kubernetes/kubernetes/pull/63049), [@andrewsykim](https://github.com/andrewsykim))
* kubelet: fix hangs in updating Node status after network interruptions/changes between the kubelet and API server ([#63492](https://github.com/kubernetes/kubernetes/pull/63492), [@liggitt](https://github.com/liggitt))

- If an old pod spec has used image volume source, we must allow it when updating the resource even if the feature-gate ImageVolume is disabled. ([#126733](https://github.com/kubernetes/kubernetes/pull/126733), [@carlory](https://github.com/carlory)) [SIG API Machinery, Apps and Node]

* Fix AWS NLB security group updates where valid security group ports were incorrectly removed ([#68422](https://github.com/kubernetes/kubernetes/pull/68422), [@kellycampbell](https://github.com/kellycampbell))
    * when updating a service or when node changes occur.
* Fix scheduling starvation of pods in cluster with large number of unschedulable pods. ([#72619](https://github.com/kubernetes/kubernetes/pull/72619), [@everpeace](https://github.com/everpeace))

- All api-server log request lines in a more greppable format. ([#87203](https://github.com/kubernetes/kubernetes/pull/87203), [@lavalamp](https://github.com/lavalamp)) [SIG API Machinery]
- Azure VMSS LoadBalancerBackendAddressPools updating has been improved with sequential-sync + concurrent-async requests. ([#88699](https://github.com/kubernetes/kubernetes/pull/88699), [@feiskyer](https://github.com/feiskyer)) [SIG Cloud Provider]